Abrasive detergent compositions



Patented Jan. 17, 1950 ABRASIVE DETERGENT COMPOSITIONS Casimir J.Munt-er, Upper St. Clair Township,

Allegheny County, Pa., assignor to Hall Laboral. i

tories, Inc., Pittsburgh, Pa., a corporation of Pennsylvania No Drawing.Application June 1, 1945, Serial No. 597,157

8 Claims. 1

This invention relates to improved detergents suitable for personal andother uses, and more particularly to compositions containingwaterinsoluble crystalline alkali-metal metaphosphate.

An object of my invention is to provide a detergent or cleanser which isnon-hygroscopic and which can be readily packed in ordinary containerswithout taking special precautions to prevent moisture absorption.

Another object of the invention is to provide a detergent compositionthat is initially freeflowing and will remain free-flowing over longperiods of time so that it can be readily dispensed from the ordinarytype of dispensing mechanism without difficulty.

A still further object of my invention is to provide a detergentcomposition containing soap which has an improved lathering power andimproved detergent qualities, and which will be non-irritating to theskin.

The glassy alkali-metal metaphosphates also known as alkali-metalphosphate glasses are widely known for their efiectiveness in hard waterbecause of their ability to soften Water on the sequestration principleas disclosed in Hall Patent Re. 19,719. The glassy phosphates arehygroscopic and for that reason are not suitable for mixing with soap,in powder, flake, or bar form, or in liquid soaps, because ofrehydration of the phosphate wholly or in part to orthophosphate withresultant loss of sequestering power and a deleterious effect on thesoap because of the development of acidity. The glassy alkali-metalmetaphosphates being hygroscopic, the moisture absorbed thereby wouldnaturally destroy the free-flowing qualities of a dry mixed detergentcomposition containing these materials and soap containing water.

I have found that desirable detergent compositions can be prepared byusing the water-insoluble crystalline metaphosphates since thesematerials are not hygroscopic and consequently a finely dividedfree-flowing composition will remain substantially unchanged in formuntil it is used. It has been found that the water-insoluble crystallinesodium metaphosphates can be solubilized by potassium, lithium, andammonium compounds and that the water-insoluble crystalline potassiummeta'phosphates can be solubilized by sodium, lithium, and ammoniumsalts. Therefore, if I prepare a detergent composition containing asodium soap of a fatty acid, I use a water-insoluble crystallinepotassium metaphosphate or a mixture of this potassium salt and thewater-insoluble crystalline sodium metaphosphate. If I employ apotassium soap of a fatty acid in my detergent composition, I use thewater-insoluble crystalline sodium metaphosphate or I may use a mixtureof this salt with the water-insoluble crystalline potassiummetaphosphate. In both cases, the alkali-metal of the soap acts in sucha way as to solubilize the normally water-insoluble phosphates.

In ordinary detergent compositions which employ alkaline softeningcompounds that precipitate the hardness minerals from water, the soaplather is quickly broken by the formation of calcium and magnesium soapswhich are water-insoluble. By solubilizing the water-insolublephosphates used in my composition, water softening is obtained and it isbelieved that watersoluble complexes are formed with the hardnessminerals of the water. There is no precipitation of the insolublemetallic soaps and full effectiveness of the detergents is madepossible.

By using the insoluble phosphates in my detergent compositions, I havefound that certain unexpected beneficial results are obtained. Forexample, since these phosphates are not instantaneously solubilized whenthe detergent is used, a certain abrasive action is noted even when Iuse only those amounts of phosphate required for sequestration ofhardness, that is to say, 10% or less by weight. The insoluble phosphateprovides a combined abrasive and sequestering action, the abrasiveaction diminishing as the phosphate solubilizes and the sequesteringaction increasing as solubilizing proceeds. In the presence of thesolubilized phosphates, the detergents seem to exhibit improveddispersing properties and the viscosity of the soap lather seems to beconsiderably greater.

The crystalline water-insoluble sodium metaphosphates may be prepared bycombining phosphoric anhydride and any suitable sodium alkali in properproportions to produce mono-sodium orthophosphate. The mono-sodiumorthophosphate is dehydrated at a temperature from about 300 to 500 C.producing the insoluble crystalline sodium metaphosphate. A process forproducing insoluble sodium metaphosphate is disclosed by Taylor andErdman in U. S. 2,356,799. The insoluble crystalline potassiummetaphosphate may likewise be produced by dehydrating mono-potassiumorthophosphate in a temperature range from 350800 C. or by combiningphosphoric anhydride and an appropriate potassium alkali to producemono-potassium orthophosphate which may be dehydrated at a temperatureof from about 350-900 C. thereby producing the crystalline potassiummetaphosphate. The potassium metaphosphate may also be produced bymelting mono-potassium orthophosphate at a temperature above 900 C. andallowing it to crystallize as it cools. In both the crystalline sodiumand potassium metaphosphate the ratio of M2OZP205 is 1:1, M being thealkali-metal of the oxide.

Generally speaking, I prefer to use from about 2-10% of crystallinewater-insoluble alkali-metal phosphates in mixtures which contain addedabrasive materials, in which mixtures I do not .epend upon thephosphates for abrasive action. Where abrasive act-ion is desired fromthe insoluble phosphates themselves, I may use as much as 407} by weightof the total mixture. Where I add both the water-insoluble crystallinesodium metaphosphate and the water-insoluble crystalline potassiummetaphosphate to a detergent composition by which I desire to obtainabrasive effect, I may use from about 2-10% by weight of potassiummetaphosphate and about 38-30% by weight of the sodium metaphosphate.The potassium metaphosphate will solubilize part of the sodiummetaphosphate while the balance of the sodium metaphosphate will remainundissolved and will produce the desired abrasive effect in thecomposition.

In preparing my detergent composition I may use from about 20% to about60% by weight of any appropriate soap of a fatty acid. For the drymixtures which may be used in a dispensing mechanism or direct from thecontainer in which they are packed. I prefer to use a finely-dividedsoap in granulated form although beads, ribbon, chips, or powder may besatisfactory. In some of my compositions I use an essentially anhydroussoap whereas in others the soap may contain about of moisture. AlthoughI prefer to use a soap having a titre in the range of from "-30 for mydry mixes, I may employ a soap having a lower titre if the final productis to be used only in cold water Where quick lathering is desired. Inmixtures which are in paste form, I prefer to employ a soft soapcontaining about -50% moisture. In most mixes, I use a sodium soap butin others. a potassium soap is employed. The soaps which are used in mypaste detergent composition have a lower titre than those which are usedin my free-flowing dry mixtures.

In some forms of detergent composition adapted for the washing of hands,I prefer to include from about 20% to about 60% by weight of an abrasivematerial which assists in removing deeply imbedded soil. I have foundthat corn meal is an excellent abrasive for this purpose, and dependingon the degree of soil to be removed, I ma use a meal of varying meshsize, the coarser mesh being preferable for removing the more tenacioustype of soil, whereas the finer mesh is suitable for moderate soil. Ihave also found that ground corn kernel husks are suitable as anabrasive for my detergent, these being used either alone or admixed withcorn meal or some other abrasive. Certain siliceous abrasives such asvolcanic ash, pumice, diatomaceous earth, finely-divided sand or othersuitable siliceous material may be used. Wood dust is also suitable asan abrasive for some of my detergent compositions.

In certain mixtures I may add an excess of a water-insoluble crystallinealkali-metal metaphosphate in finely-divided form. Part of this additionis solubilized by the alkali-metal ion of the soap or by thealkali-metal ion of one of the other ingredients in my composition. Thebalanceof the water-insoluble crystalline metaphosphate i therebyrendered available in undissolved form to act as the sole abrasiveingredicut or as one of several abrasive ingredients in my detergentcomposition.

In some of my detergent compositions I may use from about 5% to about15% by weight of a supplemental water softening agent, this agent actingnot only as a water softener but also as a mild alkali. Such phosphatesas the pyrophosphates and tripolyphosphates provide additional watersoftening and supplemental alkalinity. By using small amounts of thesesupplemental softening agents, I may reduce somewhat the amount ofcrystalline water-insoluble alkalimetal phosphate which is considerablygreater in cost than the supplemental softening agents themselves.

To most of the forms of detergent composition I prefer to add from about5% to about 10% by weight or an alkali-metal buffering agent for thecontrol of pH value. Such mild alkaline salts as sodium borate (borax),modified soda, sodium bicarbonate, and soda ash can be employed in smallquantities. .All of these compounds have mildly alkaline characteristicsand since the crystalline insoluble metaphosphates do not impartalkalinity to the composition, these buffering agents are desirable inmost instances.

In some cases, it may be desirable to incorporate from about 0.5% toabout 5.0% by weight of an antiseptic agent in the detergentcomposition. Such antiseptic agents as sodiumn-chloroparatoluenesulfonamid, commonly known as chloramine-T,n-dichloroparatoluenesulfonamid, commonly known as dichloramine-T, andsodium perborate, can be used. All of these agents have an efiect indestroying certain bacteria which may be present on the surface that isto be washed by the detergent composition. Certain stabilizers of anorganic nature should be included in the detergent composition whererancidity of the soap is likely to develop. Such compounds as carvacroland eugenol are suitable in very small amounts, about 0.1% beingsufficient. Perfumes may also be added to any of these compositionswhere desired.

The following are typical examples of detergent A compositions which maybe prepared in accordance with my invention:

Example 1 Percent Sodium soap (20-80 mesh, essentially anpacked inordinary containers without special precautions as to moistureabsorption.

Example 11 Percent Sodium soap (20-80 mesh, essentially anhydrous) 27.5Corn meal (60-100 mesh) 50.4 Hydrated borax 40-100 mesh) 6.0

Sodium tripolyphosphate mesh, an-

hydrous) 4.0 Potassium metaphosphate 100 mesh, an-

hydrous) 10.0 Eugenol 0.1 Sodium n-chloroparatoluenesulfonamid 2.0

Essentially the same as in Example I except for addition of antisepticagent and use of a more finely ground abrasive.

Example III Percent Sodium soap (20-80 mesh, moisture) 55.0

Siliceous abrasive (100-200 mesh) 35.0 Hydrated borax (40-100 mesh) 50Potassium metaphosphate (crystalline-100 mesh) 5.0

100.0 Example [V Percent Sodium soap (20-80 mesh, 10% moisture)- 55.0Sodium metaphosphate (crystalline-100 mesh) 35.0 Potassium metaphosphate(crystalline-100 mesh) 5.0 Sodium pyrophosphate, anhydrous (80 mesh) 5.0

Abrasive characteristic derived from undissolved NaPOa crystalline.

Example V Percent Potassium soap (soft-40% water) 55.0

Sodium metaphosphate (crystalline-100 mesh) 40.0 Potassium pyrophosphate5.0

Suitable as mechanics handsoap or for cleansing painted surfaces.Abrasive efiect obtained from undissolved NaPOa; crystalline K4P2O1added for increased alkalinity and water softening power.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. An abrasive soap composition which is free flowing and substantiallynon-hygroscopic and consisting essentially of the following constituentsintimately mixed and in substantially the proportions stated by weight(a) water-soluble alkali-metal soap of a fatty acid, 20% to 6092 (b)water-insoluble crystalline alkali-metal metaphosphate, 2% to 40% (c) aninert water-insoluble finely divided abrasive, 20% to 609?, and (d) analkali-metal alkaline reacting salt, 5% to 10%, said salt being capableof buffering the pH of the composition when it is wetted with water, thealkali-metal of at least one of said constituents (a) and (d) being suchas will solubilize the water-insoluble alkali-metal metaphosphate whenthe abrasive composition is wetted with water.

2. An abrasive soap composition which is free flowing and substantiallynon-hygroscopic and consisting essentially of the following constituentsintimatel mixed and in substantially the proportions stated by weight(a) water-soluble alkali-metal soap of a fatty acid, 205? to 60% (b)water-insoluble crystalline alkali-metal metaphosphate, 2% to 40% (c) aninert water-insoluble finely divided abrasive, 20% to 60% (d) awater-soluble alkali-metal alkaline reacting crystalline phosphate, 3%to 15 7, said phosphate having water softening properties, and (e) analkali-metal alkaline reacting pH buffering salt other than (d), 5% to10%, the alkali-metal of at least one of said constituents (a),. (d),and (e) being such as will solubilize the waterinsoluble alkali-metalmetaphosphate when the abrasive composition is wetted with water.

3. A composition according to claim 1 in which at least a part ofconstituent (b) is a waterinsoluble crystalline potassium metaphosphateconstituting from about 2% to about 10% by weight of the composition.

4. A composition according to claim 1 containing a small amount of anorganic stabilizer for preventing rancidity of the soap while instorage.

5. A finely divided free-flowing abrasive soap composition consistingessentially of from about 20% to about 50% of anhydrous sodium soap,from about 20% to about 60% corn meal, from about 2% to about 10%water-insoluble crystalline potassium metaphosphate, from about 5% toabout 15% alkali-metal tripolyphosphate, from about 5% to about 10%hydrated borax, and about 0.192 organic stabilizing agent to preventrancidity of the soap while in storage.

6. An abrasive soap composition according to claim 1 characterized bythe fact that the waterinsoluble alkali metal metaphosphate ofconstituent (b) is a mixture of water-insoluble sodium metaphosphate andwater-insoluble potassium metaphosphate.

'7. An abrasive soap composition according to claim 1 characterized bythe fact that constituent (b) is a water-insoluble sodium metaphosphate.

8. An abrasive soap composition consisting essentially of the followingconstituents intimately mixed and in substantially the proportionsstated by weight (a) water-soluble alkali-metal soap of a fatty acid,20% to 60% (b) a mixture of finely-divided water-insoluble sodiummetaphosphate and water-insoluble potassium metaphosphate, 2% to 40% (c)finely-divided abrasive of the group of abrasives consisting of cornmeal, corn kernel husks, pumice, volcanic ash, diatomaceous earth andsand, 20% to 60%,and (d) at least one alkali-metal alkaline reactingsalt of the group consisting of borates, carbonates and bicarbonates,tripolyphosphates and pyrophosphates, 5% to 10%, for buffering the pH ofthe composition when it is wetted with water.

CASIMIR J. MUNTER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number 8 Number Name Date 2,191,199 Hall Feb. 20,1940 2,296,121 Smith Sept. 15, 1942 2,374,100 Jackson Apr. 17, 1945 52,405,276 Taylor Aug. 6, 1946 OTHER REFERENCES Modern Soap and DetergentIndustry, Martin Crosby Lockwood & Son, London (1924), vol. 1, 10 chap,2, sec. 1, page 11,

Chemical Formulary, Bennett, Chem. Pub. Co., N. Y v01. 6, (1943), page450.

Oil, Paint & Drug Reporter, June 28, 1943, page 52.

5. A FINELY DIVIDED FREE-FLOWING ABRASIVE SOAP COMPOSITION CONSISTINGESSENTIALLY OF FROM ABOUT 20% TO ABOUT 50% OF ANHYDROUS SODIUM SOAP.FROM ABOUT 20% TO ABOUT 60% CORN MEAL, FROM ABOUT 2% TO ABOUT 10%WATER-INSOLUBLE CRYSTALLINE POTASSIUM METAPHOSPHATE, FROM ABOUT 5% TOABOUT 15% ALKALI-METAL TRIPOLYPHOSPHATE, FROM TO ABOUT 15% TO ABOUT 10%HYDRATED BORAX, AND ABOUT 0.1% ORGANIC STABLIZING AGENT TO PREVENTRANCIDITY OF THE SOAP WHILE IN STORAGE.